The fabrication of such a thin film solar cell panel as described above includes the steps of: receiving a glass plate on which a transparent electrode film (i.e., TCO film) is formed; forming scribe lines in the transparent electrode film with a laser; forming, on the transparent electrode film, a semiconductor photoelectric conversion layer from silicon and the like through CVD; forming scribe lines in the semiconductor photoelectric conversion layer with the laser; forming a conductor film on the semiconductor photoelectric conversion layer; and forming scribe lines in the conductor film and the semiconductor photoelectric conversion layer with the laser. After these steps are performed, a glass plate is affixed to the back side. Prior to affixing the glass plate, cleaning work is necessary for removing particles. As shown in FIG. 6C, if particles 99 are adhered to the inside of a scribe line 102, then insulation failure occurs between photoelectric conversion element layers (photoelectric conversion cells) 101 which are serially connected. As a result, an intended amount of power generation cannot be obtained. In this respect, conventionally, a roller brush has been used for removing particles from the inside of scribe lines (see Non Patent Literature 1, for example). The roller brush is used in the following manner: press the brush that is rotating into a scribe line while applying a cleaning liquid to the brush; and then move the target for cleaning in relation to the brush, thereby scrubbing particles away from the inside of the scribe line.
As one of conventional cleaning devices using such a roller brush, there is proposed a cleaning device as follows: a thin film solar cell panel, which is a target for cleaning, is placed on a conveyor such that scribe lines, which divide the solar cell panel, are parallel to the running direction of the conveyor; the conveyor runs, and as a result, the solar cell panel is guided into a water cleaning chamber; in the water cleaning chamber, a conductive brush is set to face the upper face of the conveyor, and cleaning water is jetted out from nozzle holes of a jet nozzle mechanism; and accordingly, while the conveyor is running, the solar cell panel is cleaned with the cleaning water jetted out from the nozzle holes, and the tip of the conductive brush slides on a photoelectric conversion cell collection area and its peripheral areas of the solar cell panel, thereby rendering these areas electrically conductive and keeping their electric potentials equal (see Patent Literature 1, for example).